Well from what I read on the XM website they are merging. So seems like we all get the best of both worlds. I have XM now and I love it I hope it stays great.
I personally think that they will remain seperate services, kinda like sprint/nextel. They stand to make more money if you have to choose one or the other, but I dont think the government is going to like it much because they are the only two sattelite radio companies and that is a huge monopilization. Id be surprised if the gov. allowed such a transaction.
They both will, assuming the deal goes through. The repetitive channels will be eliminated (ie. only one 70's channel, only one 80's channel, etc.). I assume they will go with whichever one they feel is the better suited.